The present invention relates to cationic surfactants, process for producing the same and utilization thereof. Specifically novel cationic surfactants of high biodegradability derived from hexose, process for producing the same and utilization thereof.
Cationic surfactants have been used as a softener for textiles, rinse for shampoo and hair treatment, or a bactericide. Those cationic surfactants contain quaternary ammonium salt and thus their poor biodegradability has been a serious disadvantage. Among those, alkyl trimethyl ammonium chlorides and dialkyl dimethyl ammonium chlorides that have been popular surfactants are being regulated in Europe, especially in Netherlands, because of their low biodegradability. The regulation in Europe has been advancing toward the use of the compounds having at least one ester, a decomposable group, in their molecular structure. Under such social condition, developing more biodegradable cationic surfactants is an utmost need not only from the viewpoint of safety (non-toxic to skin etc.) but also from the viewpoint of environmental protection.
Although the conventional development trend of cationic surfactants has been concentrated on the surfactants having a molecular structure in which esters are introduced into alkyl chains, it is more advantageous to develop compounds derived from natural sugars for meeting the current trend toward surfactants of higher biodegradability. The inventors of the present invention investigated on deriving cationic surfactants from the amine derivatives of reducing sugar of glucose or the amine derivatives of hexose alcohols that are reducing alcohol of hexose. As the result, the inventors found the cationic compound of superior biodegradability produced by esterifying a quaternary salt, which is a derivative of 1-amino-hexose alcohol produced by the reaction (reductive amination) of glucose or other hexose (a reducing sugar) with ammonia or primary amines, with a fatty acid.
The object of the present invention is to provide highly biodegradable new cationic surfactants produced from natural raw materials.
Another object of the present invention is to provide a profitable industrial process for producing the above cationic surfactants of the present invention.
Further object of the present invention is to provide fiber being treated with the above cationic surfactant of the present invention and having superior water absorptiveness and antistaticity and low friction.
Yet further object and advantage of the present invention are illustrated in the following description.
The above object and advantage of the present invention are, first, achieved by a cationic surfactant represented by the following formula (1),
R1xe2x80x94CH2xe2x80x94(CHR1)4xe2x80x94CH2xe2x80x94N+(R2)3Xxe2x88x92xe2x80x83xe2x80x83(1)
wherein five R1s are hydroxyls or their esters independently to each other, three R2s are hydrocarbons having 1 to 6 carbon atoms and can contain hydroxyls or esters independently to each other, Xxe2x88x92 is an anion of halogen atoms, hydrogen sulfate or organic acid, and at least one of the five R1s is an ester.
The above object and advantage of the present invention are, secondly, achieved by a process for producing cationic surfactant (hereinafter referred to as the first production process of the present invention), wherein a cationic surfactant represented by the above-mentioned formula (1) is produced through the following steps,
(A) reacting 1-amino hexose alcohol represented by the following formula (2)
HOxe2x80x94CH2xe2x80x94(CH.OH)4xe2x80x94CH2xe2x80x94NH2xe2x80x83xe2x80x83(2)
xe2x80x83with a halide represented by the following formula (3)
R2xe2x80x94Xxe2x80x83xe2x80x83(3)
xe2x80x83wherein R2and X are the same as defined in the above formula (1) to produce an ammonium salt of N-hydrocarbon-1-amino hexose alcohol represented by the following formula (4)
HOxe2x80x94CH2xe2x80x94(CH.OH)4xe2x80x94CH2xe2x80x94N+(R2)3Xxe2x88x92xe2x80x83xe2x80x83(4)
xe2x80x83wherein R2 and X are the same as defined in the above formula (1); and
(B) reacting the above ammonium salt of N-hydrocarbon-1-amino hexose alcohol with an acid halide.
And the above object and advantage of the present invention are, thirdly, achieved by a process for producing cationic surfactant (hereinafter referred to as the second production process of the present invention), wherein a cationic surfactant represented by the above-mentioned formula (1) is produced through the following steps,
(A) reacting 1-amino hexose alcohol represented by the above formula (2) with a halide represented by the above formula (3) to produce an ammonium salt of N-hydrocarbon-1-amino hexose alcohol represented by the above formula (4); and
(Bxe2x80x2) reacting the above ammonium salt of N-hydrocarbon-1-amino hexose alcohol with an organic acid in dehydration condensation.
Further the above object and advantage of the present invention are, fourthly, achieved by a process for producing cationic surfactant (hereinafter referred to as the third production process of the present invention), wherein a cationic surfactant represented by the above-mentioned formula (1) of which one of the three R2s is a methyl and other two are hydrocarbons that can contain hydroxyls or esters is produced through the following steps,
(Axe2x80x2) reacting N-methyl glucamine represented by the following formula (5)
HOxe2x80x94CH2xe2x80x94(CH.OH)4xe2x80x94CH2xe2x80x94NH.CH3xe2x80x83xe2x80x83(5)
xe2x80x83with a halide represented by the above formula (3) to produce an ammonium salt of N-hydrocarbon-1-amino hexose alcohol represented by the above formula (4) of which one of the three R2s is a methyl and other two are hydrocarbons that can contain hydroxyls or esters; and
(Bxe2x80x3) reacting the above ammonium salt of N-hydrocarbon-1-amino hexose alcohol with an acid halide.
Finally the above object and advantage of the present invention are achieved with the textile treated with the above cationic surfactants of the present invention.
The cationic surfactants of the present invention are represented by the above formula (1), wherein each of five R1s is a hydroxyl (xe2x80x94OH) or its ester independently to each other. The ester is represented by the formula, RCOOxe2x80x94; in which R is preferably a straight or branched chain and saturated or unsaturated hydrocarbon having 5 to 28 carbon atoms and may contain aromatics. The examples of such hydrocarbon are alkyls, such as pentyl, hexyl, heptyl, octyl, nonyl, decyl, lauryl, myristyl, cetyl, stearyl, eicosanyl and hexacosanyl; and their correspondent alkenyls, such as pentenyl and hexenyl.
Each of the three R2s in formula (1) is a hydrocarbon having 1 to 6 carbon atoms and may contain hydroxyls or esters independently. The hydrocarbon having 1 to 6 carbon atoms may be straight or branched chain and saturated or unsaturated. The examples of such hydrocarbon are alkyls, such as methyl, ethyl, propyl, butyl, pentyl and hexyl, and correspondent alkenyl or alkynyls having 2 to 6 carbon atoms.
The Xxe2x88x92 is an anion of halogen atoms, hydrogen sulfate (HSO4xe2x88x92) or organic acids (RCOOxe2x88x92). The examples of preferable halogen anions are fluorine anion, chlorine anion, bromine anion and iodine anion. The examples of preferable anions of organic acids are those having 2 to 12 carbon atoms, i.e., monobasic acid anions, such as acetic acid an ion and propionic acid anion; dibasic acid anions, such as oxalic acid and malonic acid; and anions of oxyacid, such as citric acid and malic acid.
At least one of the five R1s of the cationic surfactant represented by the above formula (1) must be an ester, such as monoesters, di-esters, trimesters, tetra-esters and penta-esters.
Among the compounds represented by the above formula (1), the compound of which all of three R2s in formula (1) are methyls as represented by the following formula (6),
R1xe2x80x94CH2xe2x80x94(CHR1)4xe2x80x94CH2xe2x80x94N+(CH3)3.Xxe2x88x92xe2x80x83xe2x80x83(6)
wherein R1 and Xxe2x88x92 are the same as defined in the above formula (1), is preferable because of its superior biodegradability to that of others.
The cationic surfactants of the present invention represented by the above formula (1) are preferably produced in the above first, second and third production processes of the present invention.
The step (A) of the first production process produces the ammonium salt of N-hydrocarbon-1-amino hexose alcohol represented by the formula (4) by reacting 1-amino hexose alcohol represented by the formula (2) and a halide represented by the formula (3).
The examples of the halides represented by the formula (2) are the chlorides, bromides and iodides of alkyl, alkenyl and alkynyls having 1 to 6 carbon atoms.
Then the step (B) produces the cationic surfactants represented by the formula (1) by reacting the above product in the step (A) with an acid halide (RCOX1).
The reaction occurs between the hydroxyls (xe2x80x94OH) of the product in the step (A) and acid halide (RCOX1) to produce esters (RCOOxe2x80x94). The esters (RCOOxe2x80x94) are the R1s, which represent esters in the formula (1).
The examples of the above acid halides are saturated fatty acid halides, such as caproyl halide, capriroyl halide, capryl halide, lauroyl halide, miristoyl halide, palmitoyl halide and stearoyl halide; and unsaturated fatty acid halides correspondent to them.
The steps (A) and (B) are known reaction processes, the reaction of aminos into quaternary compounds and esterification.
The second production process of the present invention consists of the step (A), which is the same as the step (A) of the first production process, and the step (Bxe2x80x2) which produces the cationic surfactants represented by the formula (1) by reacting the product in the step (A) with an organic acid in dehydration condensation.
The organic acids are represented by RCOOH. And the examples of such acids are saturated fatty acids, such as caproic acid, enanthic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid and montanic acid; and their correspondent unsaturated fatty acids.
The product can be dehydrated by heating with acidic catalysts, such as sulfuric acid, paratoluene sulfonic acid, hydrochloric acid and resins of high acidity.
In the third production process, the step (Axe2x80x2) produces the compound represented by the formula, HOxe2x80x94CH2xe2x80x94(CH.OH)4xe2x80x94CH2xe2x80x94N+(CH3) (R2)2Xxe2x88x92, wherein R2 and Xxe2x88x92 are the same as defined in the above formula, i.e., the ammonium salt of N-hydrocarbon-1-amino hexose alcohol represented by the above formula (4) wherein one of the three R2s is a methyl and other two are hydrocarbons that can contain hydroxyls or esters by reacting N-methyl glucamine represented by the formula (5) with a halide represented by the formula (3).
The step (Bxe2x80x3) reacts the product in the step (Axe2x80x2) with an acid halide to produce a cationic surfactant represented by the above formula (1) wherein one of the three R2s is a methyl and other two are hydrocarbons that can contain hydroxyls or esters. In this step, the preferable temperature and time for the reaction to produce monoesters, diesters or triesters with an acid halide, such as fatty acid halide having 12 to 18 carbon atoms, are several degrees, such as five degrees, in Celsius and several hours, such as 3 to 6 hours.
The cationic surfactants of the present invention or their mixture with conventional cationic surfactants can impart softness and antistaticity to textile yarns and fabrics and decrease the friction on their surface with known application process (usually applying with absorption or padding to 0.005 to 3 weight percent of fiber weight.). The hair-caring toiletries, such as rinse or treatment produced by adding the cationic surfactants to known oil ingredients, such as vegetable oils or liquid paraffin, function similarly to impart similar effect (usually at 1 to 5% of hair weight) to hair.